Suspended InAs Nanowire-Based Devices for Thermal Conductivity Measurement Using the 3ω Method

We demonstrated device architectures implementing suspended InAs nanowires for thermal conductivity measurements. To this aim, we exploited a fabrication protocol involving the use of a sacrificial layer. The relatively large aspect ratio of our nanostructures combined with their low electrical resistance allows to exploit the four-probe 3ω technique to measure the thermal conductivity, inducing electrical self-heating in the nanowire at frequency ω and measuring the voltage drop across the nanostructure at frequency 3ω. In our systems, field effect modulation of the transport properties can be achieved exploiting fabricated side-gate electrodes in combination with the SiO2/Si ++ substrate acting as a back gate. Our device architectures can open new routes to the all-electrical investigation of thermal parameters in III-V semiconductor nanowires, with a potential impact on thermoelectric applications.